本教程操作环境：windows7系统、php7.1版、dell g3电脑
1、使用get_headers函数
php自带的get_headers函数可以获取服务器响应一个http请求所发送的所有标头，我们可以尝试用该函数实现。
function get_redirect_url($url){ $header = get_headers($url, 1); if (strpos($header[0], ’301′) !== false || strpos($header[0], ’302′) !== false) { if(is_array($header['location'])) { return $header['location'][count($header['location'])-1]; }else{ return $header['location']; } }else { return $url; } }
2、使用fsockopen()内置函数
function get_redirect_url($url){ $redirect_url = false; $url_parts = @parse_url($url); if (!$url_parts) return false; if (!isset($url_parts['host'])) return false; if (!isset($url_parts['path'])) $url_parts['path'] = ‘/’; $sock = fsockopen($url_parts['host'], (isset($url_parts['port']) ? (int)$url_parts['port'] : 80), $errno, $errstr, 30); if (!$sock) return false; $request = “head ” . $url_parts['path'] . (isset($url_parts['query']) ? ‘?’.$url_parts['query'] : ”) . ” http/1.1\r\n”; $request .= ‘host: ‘ . $url_parts['host'] . “\r\n”; $request .= “connection: close\r\n\r\n”; fwrite($sock, $request); $response = ”; while(!feof($sock)) $response .= fread($sock, 8192); fclose($sock); if (preg_match(‘/^location: (.+?)$/m’, $response, $matches)){ return trim($matches[1]); } else { return false; }}
3、使用curl函数
function get_redirect_url($url, $referer=”, $timeout = 10) { $redirect_url = false; $ch = curl_init(); curl_setopt($ch, curlopt_url, $url); curl_setopt($ch, curlopt_header, true); curl_setopt($ch, curlopt_nobody, true);//不返回请求体内容 curl_setopt($ch, curlopt_followlocation, true);//允许请求的链接跳转 curl_setopt($ch, curlopt_returntransfer, true); curl_setopt($ch, curlopt_timeout, $timeout); curl_setopt($ch, curlopt_httpheader, array( ‘accept: */*’, ‘user-agent: mozilla/4.0 (compatible; msie 6.0; windows nt 5.1; sv1)’, ‘connection: keep-alive’)); if ($referer) { curl_setopt($ch, curlopt_referer, $referer);//设置referer } $content = curl_exec($ch); if(!curl_errno($ch)) { $redirect_url = curl_getinfo($ch, curlinfo_effective_url);//获取最终请求的url地址 } return $redirect_url;}
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以上就是php获取重定向url的几种方法是什么的详细内容。